at \(Q_0^2 = 4~\mathrm {GeV}^2\) . In the polarized case we use the fit to \(x g_1^{\rm NS}(x,Q_0^2)\)  of the structure
function
of Ref. [1]} at \(Q_0^2 = 10~\mathrm {GeV}^2\) ,
\(x g_1^{\rm NS}(x,Q_0^2) &=& 2.4312 \cdot 10^{-5} x^{-0.38573} (1-x)^{2.69522}\nonumber \\ && \times (-1+279.624 \sqrt{x} + 1239.76 x + 7053.93x^{3/2} + 1866.208 x^2)\) 
<FIGURE>